Register for and file your Self Assessment tax return

Register if you're not self-employed

If you have to send a tax return and did not send one last year, you need to register for Self Assessment by 5 October.

After you register

You’ll get a letter containing your Unique Taxpayer Reference (UTR) within 10 working days (21 if you’re abroad). You need your UTR to send a return.

If you’ve sent a Self Assessment tax return before, you’ll already have a UTR. If you do not know it, you can wait for the letter or find your UTR.

If you’ve sent a return online before

Once you’ve re-registered, sign in to your existing account to send a return.

If you have not sent a return online before

After you register, you’ll need to:

You’ll get an activation code in the post within 7 working days of signing up (21 if you’re abroad). When you get the code, sign in to send your return.

You can replace an activation code if you do not receive it or you lose it.